Microwave oven



FIG. 1 is a perspective view of a microwave oven of the present invention;

FIG. 2 is a front view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a left side view thereof; and,

FIG. 6 is a right side view thereof.

The broken lines shown represent the portions of the microwave oven that form no part of the claimed design. 

CLAIM The ornamental design for a microwave oven, as shown and described. 